*3.5. Cryptorchidism*

Cryptorchidism, or undescended testis, is a well-known risk factor for male infertility and a common genitourinary finding. This disorder affects 1–9% of all male neonates worldwide, with approximately 3% of boys remaining cryptorchid at one year of age [36,37]. Semen abnormalities are observed in up to 30% of men with a history of unilateral cryptorchidism and up to 80% of men with a history of bilateral cryptorchidism [38]. Recommended treatment is orchidopexy, or fixation of the testis within the scrotum, and typically is performed early in life (by 18 months of age) to prevent future testicular dysfunction [36,39,40]. The majority of men with a history of cryptorchidism, either unilateral or bilateral, are fertile, however some may develop azoospermia secondary to iatrogenic injury to the testis or testicular vasculature during orchidopexy, or baseline underlying severe spermatogenic dysfunction. For men with NOA secondary to cryptorchidism, testicular sperm extraction is generally favorable with success in the majority of these patients [41–46].
